Iroko Tree (Uko)
Statistics and Facts
IMAGE: Iroko Tree »
The Iroko tree (Yoruba) also known as Uko in Igbo, is a wonderful tree both in Legends and in actual modern uses. Its scientific name is "Chlorophora excelsa", it is of the mulberry family and has strong streaky insect-resistant wood which is often used as a teak substitute.
At home in the Tropics of Africa, especially on the West Coast, it is a large hardwood. It is sometimes called Nigerian or African Teak, although it is not of the teak family. The wood starts as yellow but darkens to a rich brown over time. The Iroko tree is found in Angola, Benin, Cameroon, Congo, Ghana, Guinea, Mozambique under different names like Kambala, Mvule, Abang, Doussie, Odum, Intule, Tule etc.
The tree grows to an average height of 50 meters (164 feet) and is normally between 75 cm (2.3feet) to 250 cm (8.2 feet) in diameter. The tree-stem averages between 15 to 28 meters branch-free. Iroko looks vagely similar to teak. This is why it is sometimes called African-teak or Kambala-teak, a misleading European name.
In many cultures the tree is feared, shunned or revered. Yoruba's believe that the tree is inhabited by a spirit - The Iroko-Man, legend has it that anyone who sees the Iroko-Man face to face goes insane and soon dies. In Yoruba culture, a man who cuts down an Iroko tree brings bad luck to himself and his family. They believe that the spirit of the Iroko can be heard in homes that use Iroko wood, because the spirit of the Iroko is trapped in the wood.
Iroko wood is used in many applications like cabinetmaking, boat-construction, domestic flooring, furniture and paneling as a substitute for teak, which it resembles both in colour (light brown to deep golden-brown) and in grain. It is very durable because it is rot and insect resistant. It is also used in some musical instruments due to its lively sound.
Additionally, its roots and leaves are medicinal, it is also used for "local" twig toothbrushes and of course its branches burn slowly and are a good source of cooking firewood and its fruits are loved by Bats and Monkeys.
Its usefulness is further aided by its wide availability, no trade restrictions and the small amount of adverse effects from Iroko dust, limited to asthma, dermatitis and nettle rash.
It is a strong candidate in the fight against carbon emission because Iroko trees are one of the species of African trees that can turn carbon in the atmosphere into mineral limestone. In the United Nations Special Rapporteur on the right to food, Oliver de Schutter, states that the Iroko tree serves as a long-term carbon sink and can play a strong role in the fight against climate change. The microbes in an Iroko tree, can turn carbon dioxide emissions into soil-enriching limestone, a process that kills 2 birds with 1 stone: carbon dioxide is ejected from the atmosphere, and acidic, dry soil is made fertile for agriculture.
FORMULATION AND DESCRIPTIONS
The wood is tough, dense, and very durable. It is a hardwood and does not require regular treatments with oil or varnish when used in outdoor applications.
Straw-coloured flying fox (Eidolon helvum)
Photograph: David Liebman, Lubee Bat Conservancy
It fruits Grow in drupes (they contain one or more seeds inside) and are surrounded by fleshy fruit on the outside. The fruits are usually about finger length and can be compared to mulberries. They are loved by Bats and Monkeys, infact the proliferation of the Iroko tree can by largely credited to Bats, as they litter the grounds with the trees during flight.
It survives in both lush and hash environments and can tolorate dry land but not long and intense droughts.
Its Stems are tall, straight, and cylinder shaped. There are usually no branches on the trunk until about 30 meters from the ground. The bark is a medium to dark grayish brown.
It Buds appear small and bulbous and are often found in small clumps.
Its Leaves are full and bunched in large clusters on the upper branches, giving the tree a wide canopy. They range from medium to dark green in color and are mostly oval in shape.
It has Flowers which are both male and female although they grow independently and separate from each other. The flowers themselves have four petals and fully erect stamens.
OTHER QUICK FACTS
Scientific Name: Chlorophora excelsa
Trade Name: Harwood, Iroko
Family Name: Moraceae
Common Names: African Teak, Kambala, Mvule, Abang, Doussie, Odum, Intule, Tule
Regions of Distribution: These trees are found in Tropical Africa
Countries of Distribution: Gambia, Ghana, Cameroon, Sierra Leone, Nigeria, Angola, Zaire.
--- Appearance ---
Color: The wood displays a yellowish hue which darkens to a rich brown as the wood ages. If untreated, the wood will turn to a silvery-grey color.
Grain: Extremely interlocked and irregular grain with a medium to coarse texture.
Variations with species and grades: There are very wide variations between the different species.
--- Properties ---
Hardness/Janka: Fairly hard wood with a Janka rating of 1260
Dimensional stability: This wood has an excellent stability. It dries rapidly with very little shrinkage.
Origin: Iroko trees are only found in Africa
Availability: Moderate availability.
Average and maximum lifespan: The average lifespan of an Iroko tree is approximately two hundred years, although there are trees on recorded that are as old as four hundred years.